Once sidelined, Eli Lilly's COVID-19 antibody treatment is on the comeback trail with new $1.3B supply agreement

After a two-month hiatus, Eli Lilly’s COVID-19 antibody treatment is back in the game and hoping for a successful second chapter.

On Tuesday, the company revealed that it's has struck a deal with one of its loyal customers, the United States government, which has agreed to purchase 614,000 doses of the therapy for $1.29 billion.

The combination of etesevimab and bamlanivimab is a treatment for mild to moderate COVID-19 or for post-exposure prophylaxis in high-risk individuals. Lilly will provide at least 400,000 doses by the end of the year, with the rest guaranteed by the end of January 2022.

A year ago, Lilly’s combo was the first antibody therapy to gain emergency use authorization for the treatment of COVID-19. But by the spring, the FDA began sidelining the medicine in some states because of its ineffectiveness against variants, primarily the gamma first found in Brazil and the delta-plus first identified in India. In June, the U.S. regulator halted all distribution of the treatment.

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In August, the FDA reactivated the authorization but restricted use of Lilly’s antibodies to states where certain variants accounted for less than 5% of cases. At that time, the nod opened use of the treatment in more than 20 states. Last week, when the FDA released (PDF) its updated list of states and U.S. territories under the 5% threshold, all were included and eligible for Lilly’s antibodies.

Now it’s up to Lilly to play catch up. In the absence of the company’s treatment, Regeneron’s antibodies gained favor. In the second quarter, when Lilly’s antibody sales fell to $149 million after exceeding $800 million in each of the previous two quarters, Regeneron’s sales skyrocketed to $2.6 billion. Regeneron is scheduled to reveal its third-quarter earnings on Thursday.

RELATED: Regeneron's COVID-19 antibodies rake in $2.6B, reflecting their market dominance and blowing away estimates

Now, Lilly has another COVID-19 antibody player to contend with in GlaxoSmithKline and Vir Biotechnology. In May, the FDA sanctioned their treatment, sotrovimab. Last week, GSK reported (PDF) third-quarter sales of $156 million for its antibodies. In an SEC filing in September, Vir said that agreements have been made for the sale of more than 420,000 doses of sotrovimab, including a "portion of those procured by the U.S. government."

Meanwhile, even though Lilly's drugs will see continued use in the U.S., the company pulled its application to the European Medicines Agency for the combo. The company said that because of low demand there, it's "not in a position to generate the additional data" needed to proceed with its EMA application.